Roof coating is a liquid-applied membrane rolled or sprayed over a low-slope roof after a roof condition survey. We prime chalky or bare substrate first, then check wet film thickness as we go — dry film thickness is what decides how long the roof lasts.
For a building owner, the math is straightforward. A silicone coating costs a fraction of a tear-off, cures to a reflective finish that lowers rooftop surface temperature, and holds up where ponding water sits for days after a storm.
Acrylic elastomerics cost less and breathe well over asphalt, but they cannot sit in standing water. Silicone and polyurethane coatings handle that. Cure time matters here — a summer thunderstorm or a winter ice dam will find any area that has not fully set.
What we look for before quoting a coating
- Alligatoring and widespread cracking on a dried-out modified bitumen cap sheet mean the surface needs primer, not a second layer of tar.
- Chalking and peeling say the old surface is releasing, and a coating laid over it will delaminate inside a season.
- Blistering, or blistered pockets that flex underfoot, usually points to moisture trapped in the insulation below the membrane.
- Granule loss and surface erosion on a built-up roof leave bitumen exposed to UV degradation that keeps eating the surface.
- A soft or sagging roof deck rules coating out entirely; we would be coating over decay rather than covering it.
Materials that hold up in this climate
- Silicone coating is our default over ponding water because it stays flexible and shrugs off UV degradation.
- Acrylic coating costs less and suits sloped metal panels, though it chalks faster under strong summer sun.
- Polyurethane coating adds tensile strength and scuff resistance where foot traffic crosses the roof to reach a rooftop unit.
- Elastomeric coating bridges hairline cracks and moves with the deck as it expands and contracts through the year.
- Gaco (Sika) silicone systems, GAF EverGuard TPO and silicone systems, plus Henry and Tropical Roofing products, give us published coverage rates to quote against.
- Primer systems do the quiet work: a bonding primer on rusted steel or a chalked cap sheet prevents an adhesion failure later.
Which roofs we coat, and which we do not
- Coating fits sound TPO, EPDM, PVC membrane, modified bitumen and built-up roof assemblies with intact flashing and drainage.
- Coating does not fix asphalt shingle, architectural shingle or three-tab shingle fields, where a shingle roof simply needs replacement.
- Coating does not restore wood shake, cedar shake, slate, clay tile or concrete tile, and it never belongs over a failing substrate.
- Coating over metal panel, standing-seam panel or corrugated panel works when seams are sound and fasteners are hand-sealed first.
We recoat the easy-to-forget details too: parapet walls, coping, scuppers, counter-flashing, apron flashing, pipe boots and drip edge at the eave. A coated field with a dry, uncoated pipe flashing will still leak.
If a roof inspection turns up a soft substrate, rot or a failed chimney flashing, we say so and quote the repair instead. Coating a roof that needs replacement wastes your money. Call 877-909-0534 for a free estimate, including emergency work.
